The guy has a fantastic voice but I wonder if the wedding was more about him than the couple being married.
I understand your point. But I imagine many weddings feature a wedding singer. And if they do, it's probably good to have a capable vocalist. I suppose a good singer invariably steals a bit of the bride and groom's thunder. So if it's going to happen, and you get married in a church, then it might as well be the priest. Cuts down on the clutter.